Four Manhattan residents who were trampled in a stampede that was started when a gunman opened fire into the crowd during a hip-hop show are suing a downtown music venue for failing to do enough to prevent the mayhem.

Richard Allen, Kamaal Allen, Trent Lee and Tirell Nickens were injured and traumatized in the Sept. 12, 2013, melee at Sounds of Brazil, better known as S.O.B.’s, on Varick Street, when shots were fired by an unidentified gang member, according to the suit the men plan to file in Manhattan Supreme Court on Monday.